The present invention relates to an enhancer of immunological functions which increases human interferon production and enhances human immunological functions.
Interferon (IFN) is produced in cells, such as leucocytes, fibroblasts and T-lymphocytes, which are infected with virus, and it protects other cells from virus infections. Thus, the interferon has an inhibitory effect on multiplication of virus.
Of the IFNs, IFN-.alpha. production has been reported to decrease in patients with cancer, diabetes, tuberculosis, etc., and the ability of IFN-.alpha. production is inversely related to the susceptibility to infection.
Further, it has also been reported that IFN-.gamma. production is decreased in patients with cancer, and increased in Hashimoto's disease, an autoimmune disease.
It is also known that IFN-.gamma. production contributes to human immune functions which differ from those reflected by IFN-.alpha. production.
Thus, the capacity of IFN-.alpha. and IFN-.gamma. production is considered to be a useful parameter of evaluating immunological functions of individual.
It is thought that the enhancement of these immunological functions might improve the general condition and the quality of life of patients with impaired immunological function.
In order to enhance the immunological functions, it has been proposed to administer IFN or to utilize a strong immunopotentiator such as OK432.
There is a known correlation between Natural Killer (NK) activity and the condition of cancer patients, and it is well-known that IFN administration enhances the activity.
However, repeated use of IFN or an immunopotentiator like OK432 has been found to cause side-effects, such as an imbalance of homeostasis, pyrexia and malaise.
Therefore, instead of administering IFN, enhancers of immunological functions (IFN inducers) have been developed which increase interferon production in a human body and enhance immunological functions. In fact, double helix RNA, pyran copolymer, anionic high polymer, and kinds of polysaccharides (see Japanese Patent Publication No. Hei. 3-9882) have been already proposed as enhancers of immunological functions.
However, since these well-known enhancers of immunological functions do not naturally exist in the human body, these enhancers have some toxicities, which might cause side-effects in the human body when used in the treatment of infections or tumors.